DEV: Convert start-backup modal to component-based API (#22812)

app/assets/javascripts/admin/addon/components/modal/start-backup.hbs

@@ -0,0 +1,23 @@
+<DModal
+  @title={{i18n "admin.backups.operations.backup.confirm"}}
+  @closeModal={{@closeModal}}
+>
+  <:body>
+    {{#if this.warningMessage}}
+      <div class="alert alert-warning">{{html-safe this.warningMessage}}</div>
+    {{/if}}
+  </:body>
+  <:footer>
+    <DButton
+      class="btn-primary backup-with-uploads"
+      @action={{this.startBackupWithUploads}}
+      @label={{or this.yesLabel "yes_value"}}
+    />
+    <DButton
+      class="backup-no-uploads"
+      @action={{this.startBackupWithoutUploads}}
+      @label="admin.backups.operations.backup.without_uploads"
+    />
+    <DButton class="btn-default" @action={{@closeModal}} @label="no_value" />
+  </:footer>
+</DModal>

app/assets/javascripts/admin/addon/components/modal/start-backup.js

@@ -0,0 +1,16 @@
+import Component from "@glimmer/component";
+import { action } from "@ember/object";
+
+export default class StartBackup extends Component {
+  @action
+  startBackupWithUploads() {
+    this.args.model.startBackup(true);
+    this.args.closeModal();
+  }
+
+  @action
+  startBackupWithoutUploads() {
+    this.args.model.startBackup(false);
+    this.args.closeModal();
+  }
+}